The present invention relates generally to machines used to bore holes and tunnels underneath roads, driveways and the like for the purpose of installing plumbing and electrical conduits and other utility equipment. More specifically, the present invention includes a low-profile, portable modular boring machine that may be broken down into several component parts for purposes of transport and storage.
Many different types of earth boring machines are used to dig tunnels and ditches, particularly underneath roads and driveways, in order to install water lines, electrical lines, and other types of utility equipment. Such machines are useful for this type of work, because it obviates the need to break up sections of road, driveway, or other types of installed surfaces while the work is being performed. Years ago, if it was necessary to install a water line, for instance, beneath a road surface, workers would be required to use jackhammers and other tools of destruction to break up a section of the road. Then, workers would dig a ditch, install the water line, refill the ditch, and repair the road surface. This method was extremely inconvenient, because the work would disrupt road traffic while the work was taking place. More recently, earth boring machines have been developed that are used to simply dig a hole or tunnel underneath a road (or similar surface), which allows the work to take place without disrupting the road surface, and traffic as well, in the process. While these earth boring machines are an improvement over the earlier method of breaking up the road for such installation, they still have problems and disadvantages of their own.
U.S. Pat. No. 3,886,999, issued to Appleman, is directed to a portable earth boring machine for the horizontal boring of shafts and the insertion of pipeline casing sections in installations where excavation from the surface is undesirable. The machine is characterized by vertically adjustable auger drive means which permit the selective location of the axes of the auger drive shafts at various elevations such that augers of various diameters can be utilized without the necessity of excessively deep excavations for the installation of the machine and its track when pipe lines of smaller diameter are to be installed. The machine is further characterized by casing pusher ring apparatus arranged to selectively accommodate casing pusher rings of various diameters so as to conform with the selected size of the boring auger being used during the particular boring operation.
U.S. Pat. No. 3,907,043 describes a portable earth boring machine for the horizontal boring of shafts and the insertion of pipeline casing sections, similarly to the '999 patent listed above.
U.S. Pat. No. 3,939,926 discloses a portable earth boring machine characterized by a steering head particularly adapted for rock drilling operations which head is positioned at the front of the casing with such steering head being automatically controlled so as to directionally control the direction of extension of the pipeline as the drilling operation progresses.
U.S. Pat. No. 4,042,043 is directed to a portable earth boring machine characterized by frame means adapted for movement along a track means, which frame means supports an engine which drives an earth boring auger as well as casing pusher apparatus for pushing casing sections into the earth fill as the boring operation progresses. The machine is further characterized by a fluid actuated pusher cylinder means for advancing the auger into the earth fill and associated automatic auger feed control means for automatically maintaining a constant fluid flow rate to said pushing cylinder means under variations in resistance to auger penetration of said earth fill during a boring operation.
U.S. Pat. No. 4,538,858 discloses a horizontal earth boring machine in which a carriage supports an engine rotatably connected to an auger, and a push ring. The carriage is movable along a set of tracks between a forward position and a rearward position. Hydraulic means power the carriage between its forward and rearward positions. In one version, the auger and push ring are connected by a universal joint to the engine so that a pair of hydraulic cylinders can raise the push ring and planetary gear reduction unit to an adjusted position above the track in order to accommodate any vertical misalignment of the push ring as it is pushing pipe through a horizontal hole drilled by the auger.
U.S. Pat. No. 4,533,612 is directed to an earth boring machine for boring straight and level elongated holes through rock-laden earth. The machine includes a stationary elongated frame upon which a first slide is carried. A second slide is carried on the first slide. An elongated auger guiding sleeve is carried adjacent one end of the first slide and has a cutting edge on a remote end thereof. A power-driven auger assembly is carried on the second slide and includes an auger which extends within the guiding sleeve. A cutting tool is carried on the end of the auger adjacent a remote end of the guiding sleeve. A hydraulic cylinder is provided for advancing the first sleeve for driving the cutting edge of the guiding sleeve into the earth while the power driven auger removes the earth as the guiding sleeve is advanced. Another set of hydraulic cylinders are provided for advancing the second slide on the first slide causing the cutting tool to extend out beyond the remote end of the guiding sleeve for cutting through obstructions in the earth when the cutting edge of the guiding sleeve is prevented from moving forward.
U.S. Pat. No. 5,810,101 describes a digger for digging utility pole holes, wherein the digger is encased in an elongated box. The box has an attachment thereon for attachment to the carrying arm of a backhoe in place of the backhoe bucket. A 90° attachment provides versatility. The digger is capable of digging horizontal tunnels for laying one underground line under another underground line.
Each of the references cited above is hereby incorporated herein by reference. Unfortunately, each of these machines has disadvantages and drawbacks. Many are large, bulky and awkward, and have a large footprint, which makes them difficult to use in areas where there are bushes or other obstructions near the work area. Some require the use of large machinery, such as an excavator, which in itself is difficult and expensive to operate. Therefore, it would be desirable to provide a low profile, portable, horizontal earth boring machine of modular construction with a small footprint, which can be easily assembled on site for use, and which can be easily disassembled for transport, for instance, on a small trailer.
Additionally, in order to bore a horizontal hole under a road or driveway, it is generally necessary to dig a hole adjacent the roadway where the boring machine may be placed. Because the boring operation is generally horizontal, the hole next to the roadway must be large enough for the boring machine, plus the length of the tracks to fit into. For this reason, it is desirable to provide a small, portable horizontal boring machine, in order to minimize the size of the ditch in which the boring machine must be positioned for the boring operation.